The changing of colour oxidatively, in particular the bleaching or lightening of the natural hair colour is traditionally the desire of many consumers, since a blonde hair colour is considered to be attractive and desirable from a fashion viewpoint. For this purpose, various bleaching agents with different bleaching power are obtainable on the market. The oxidants contained in these products are able to lighten the hair fibres due to the oxidative destruction of the hair's own pigment melanin and/or artificial dyes. For a moderate bleaching effect, the use of hydrogen peroxide—optionally with use of ammonia or other alkalising agents—as sole oxidant is sufficient, however a mixture of hydrogen peroxide and peroxo salts, in particular persulfate salts, is usually used in order to attain a stronger bleaching effect.
These peroxo salts are usually used in the form of a powder that is mixed with a hydrogen peroxide preparation just before application. The use of the combination of hydrogen peroxide and persulfates is associated with various disadvantages. The application of hydrogen peroxide to the scalp may lead to irritation. Also, at least two separately packaged components (the persulfate powder and the hydrogen peroxide solution) have to be mixed with one another in order to produce the ready-to-use bleaching agent. Users, who where possible support sustainable consumerism, are also paying increased attention to the ecological aspects of a product. One objective here is also a reduction of packaging material. Products that are used in the most concentrated form possible, which include merely one component and which in order to produce the application mixture in an optimal manner have to be mixed merely with water offer a key advantage in respect of the saving of packaging material.
In addition, the lightening known from the prior art is also associated with hair damage, since not only the pigments of the hair but also the other structural constituents of the hair are oxidatively damaged. Depending on the extent of the degree of damage, this ranges from coarse, brittle hair that is difficult to comb to a reduced resistance and tensile strength of the hair, as well as splitting through to hair breakage. The longer is the reaction time and the greater is the amount of used hydrogen peroxide and peroxodisulfates, generally the more severe is the damage caused to the keratin fibres. The discovery of new bleaching agents with reduced hair damage is therefore likewise an ever-existing challenge.